English

Near perfect matchings in uniform hypergraphs

Combinatorics 2019-11-19 v1

Abstract

In this paper, we study degree conditions for the existence of large matchings in uniform hypergraphs. We prove that for integers k,l,nk,l,n with k3k\ge 3, k/2<l<kk/2<l<k, and nn large, if HH is a kk-uniform hypergraph on nn vertices and δl(H)>(nlkl)((nl)(n/k2)2)\delta_{l}(H)>{n-l\choose k-l}-{(n-l)-(\lceil n/k \rceil-2)\choose 2}, then HH has a matching covering all but a constant number of vertices. When l=k2l=k-2 and k5k\ge 5, such a matching is near perfect and our bound on δl(H)\delta_l(H) is best possible. When k=3k=3, with the help of an absorbing lemma of H\'{a}n, Person, and Schacht, our proof also implies that HH has a perfect matching, a result proved by K\" uhn, Osthus, and Treglown and, independently, of Kahn.

Keywords

Cite

@article{arxiv.1911.07431,
  title  = {Near perfect matchings in uniform hypergraphs},
  author = {Hongliang Lu and Xingxing Yu and Xiaofan Yuan},
  journal= {arXiv preprint arXiv:1911.07431},
  year   = {2019}
}
R2 v1 2026-06-23T12:18:46.762Z